Patent · US Expired

Block-level wordline enablement to reduce negative wordline stress

US5818764A · kind A · utility

26Cited by
32References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 6, 1997
Grant dateOct 6, 1998
Priority date
Expiry dateFeb 6, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C16/16
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A circuit is provided for supplying a negative erasing voltage onto the wordlines of selected blocks in an array of floating gate memory cells. The circuit includes a voltage circuit, which has a plurality of local outputs, each of which connects to wordlines of an associated block of floating gate memory cells. A block selector circuit is coupled to the local outputs of the voltage circuit and selectively switches each of the local outputs to apply either an erasing voltage or a non-erasing voltage onto the wordlines of the associated block of floating gate memory cells. Negative wordline stress is thus reduced for wordlines of unselected blocks which receive a less negative, non-erasing voltage during block erase operations.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.